Read the passage and answer the following questions:
Once inside the human body, the HIV virus enters macrophages, a type of immune cell. Within the macrophages, the viral RNA genome is replicated to form viral DNA with the assistance of an enzyme called reverse transcriptase. This viral DNA is then integrated into the DNA of the host cell, directing the infected cell to produce virus particles. The infected macrophages continue to produce the virus, acting as HIV factories. Simultaneously, the HIV virus also enters helper T-lymphocytes (TH cells) and replicates within them, producing new viruses. These progeny viruses are released into the bloodstream and target other helper T-lymphocytes, leading to a progressive decrease in their numbers. As the number of helper T-lymphocytes decreases, the infected person experiences various symptoms such as fever, diarrhoea, and weight loss. Due to the decrease in helper T-lymphocytes, the person's immune system becomes severely weakened, making them susceptible to infections that could typically be overcome, including those caused by bacteria, such as Mycobacterium, viruses, fungi, and parasites like Toxoplasma. The patient becomes immunodeficient, unable to effectively protect themselves against these infections. Enzyme-linked immunosorbent assay (ELISA) is a widely used diagnostic test for AIDS, allowing for the detection of HIV infection. While antiretroviral drugs can partially prolong the life of AIDS patients, they cannot prevent death, which is inevitable without a cure for the disease. As AIDS has no cure, prevention is the best option. HIV infection primarily spreads through conscious behavioural patterns, unlike infections like pneumonia or typhoid that may occur inadvertently. Steps such as ensuring blood safety in blood banks, using disposable needles and syringes, promoting condom distribution, controlling drug abuse, advocating safe sex, and regular HIV check-ups in susceptible populations are taken to prevent the spread of HIV infection. It is essential not to hide HIV infection or AIDS as doing so may lead to further transmission. HIV/AIDS-infected individuals deserve help and sympathy from society instead of being stigmatized. Recognizing HIV/AIDS as a collective problem and taking collaborative actions between society and the medical fraternity are needed to prevent the widespread dissemination of the disease. It requires a joint effort to tackle this malady and prevent its spread.
What is the purpose of the enzyme-linked immunosorbent assay (ELISA) test?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → To diagnose HIV infection
The passage states that “Enzyme-linked immunosorbent assay (ELISA) is a widely used diagnostic test for AIDS, allowing for the detection of HIV infection”.
ELISA is a diagnostic test. It finds out whether a person is infected with HIV; it does not treat, prevent or teach anything by itself.
Option (1) To diagnose HIV infection — Correct. ELISA is used to diagnose HIV infection.
Option (2) To prevent the spread of HIV — Incorrect. Spread of HIV is prevented by steps such as safe blood, disposable needles and syringes and the use of condoms. A test does not stop the spread.
Option (3) To prolong the life of AIDS patients — Incorrect. The passage gives this role to anti-retroviral drugs, which can partly prolong the life of AIDS patients. ELISA is a test, not a drug.
Option (4) To educate people about AIDS — Incorrect. Educating people about AIDS is the work of organisations such as NACO and NGOs, not of a laboratory test.